Step 8: Light that bad-boy up!

This instructable will show you how to easily make a functional rocket stove from recyclable cans for almost no cost.

Items you will need: 1 - No. 10 Can (Standard restaurant size can. Mine was a pineapple chunks can from a local pizza parlor. They gave it to me free.) 4 - Regular soup cans (Standard 10.75oz Campbell's Soup cans) Insulation material. I used Perlite. It's cheap and available at any garden center. I had it on hand for my garden. You can use sand, dirt, ashes, foam, any insulator.

Step 1: Mark and Cut hole in No. 10 can

Take one of the four soup cans (soup can #1) and trace the shape onto No.10 can. I cut my hole slightly above the bottom of the can to make it easier to avoid dealing with the bottom of the can when cutting and shaping the hole. Seems to have worked out fine.

I then punched a number of holes into the circle so I could get the tin snips in there to cut the circle out. Punching that many holes turned out to be a waste of time as a single hole would have been fine. The tin snips cut through the can quite easily.

I used a pair of needle nose pliers to bend the edges of the hole back to get the final shape, but in retrospect I would have probably just relied on the sharpie outline and cut the hole wider to begin with. I was somewhat conservative when cutting and widening the hole took some effort. Later can fittings were made easier by just cutting the hole to the right size to begin with. I was afraid of cutting too big to begin with and therefor spent a considerable amount of time fidgeting with it.

Step 2: Mark and cut hole in soup can #1

You are going to need to have a hole cut at the same height in soup can #1 so that a later soup can (soup can #2) will go through the No.10 can and directly into soup can #1 to form an elbow of sorts.

To do this, I placed my first soup can into the No.10 can and snugged it up next to the hole I had cut in the No.10 can. I then took a Sharpie pen and traced the hole I had already cut in the No.10 can onto the soup can. The photo is hard to make out but it is a picture of the soup can inside the No.10 can with a faint black marker outline of the hole on the soup can.

Pro tip: Make sure you have fitted a can through the No.10 can hole to make sure it fits through cleanly but somewhat snug. you don't want any big gaps, but you also don't want to trace a hole onto the soup can that is already to small to fit the next soup can you will be inserting into it.

Pull the soup can out of the No.10 can and cut out the shape drawn on it. I punched a starter hole with the hammer and nail again. I cut the shape and then rounded the edges back a bit for a snug fit.

Step 3: Cut bottom off of Soup Can #2 and fit as elbow

Take your second soup can and remove the bottom. You can do this with a can opener if you want, but I just used my tin snips. It was actually faster this way. The bottom of these cans is not like the top anymore so they don't open well with a can opener.

This (soup can #2) will be the horizontal burn chamber of the Rocket Stove.

You will want to "Dry Fit" the first two soup cans together to make sure they will fit once you assemble them inside the No.10 can. Once they fit well you can assemble these two cans inside the No.10 can.

Soup can #1 with the hole you cut into it should be placed into the center of the No.10 can with the hole in the soup can lining up with the hole in the No.10 can. The open end of soup can #1 should be facing up so that you can insert soup can #3 into it as the chimney in a later step.

Soup can #2 should go through the hole in the No.10 can and into the hole in soup can #1 to form an elbow of sorts.

Step 4: Cut and fit the Chimney from Soup Can #3

Take your third soup can (soup can #3) and remove the top and bottom and then slit it vertically from top to bottom. You will fit this as the chimney stack, inserting it into soup can #1 that is sitting inside the No.10 can.

I found that I needed to slice off about a quarter of an inch worth of excess can in order to crimp it down small enough to neatly fit inside of soup can #1. Seemed like a lot to take off just to squeeze down inside the circle of the other soup can, but it did.

I also would recommend cutting a small arch into this can where it intersects soup can #2 coming in from the side. Otherwise the chimney will be too tall when finished. I do not have a picture of this, but when I first put it all together I noticed that the chimney stuck up too high for placing anything on top. It needs to be about a quarter inch below the top of the rim of the No.10 can for proper use. I removed my chimney and cut the arch and it fit perfectly. You could just cut the can down a little and leave the arch out. It would still work fine as long as you have the proper height of the chimney in relation to the rim of the No. 10 can.

Fit the chimney properly and you are ready to move on.

Step 5: Cut a hole in the lid of the No 10. can for the chimney

Take the chimney (soup can #3) and trace the shape onto the lid of the No. 10 can. You will want to cut it out so that the chimney can pokes through the top of the stove.

This is fairly straight forward. To punch the starter hole however, it is a good idea to place the lid on a piece of wood to give the nail something to drive into. Doing it on a hard surface does not allow the nail to penetrate and doing it on dirt will bend the lid. I used a scrap piece of lumber.

Snip the hole to size and test fit the chimney.

Step 6: Assemble, Fill with insulation material, seal the lid.

With all of the parts for the stove cut and fitted, you will want to assemble the burn chamber (Soup Can #1) and the elbow (Soup Can #2) and chimney (Soup Can #3) inside the No.10 can.

Once assembled, you will want to fill the space left over with an insulator. I used Perlite, but any insulator will work fine. You can use sand, clay, foam insulation, vermiculite, ash, anything with good insulative properties. I use Perlite, in my garden, so I had it on-hand. It is basically the same sort of tiny foam balls you find inside a bean bag chair, but I don't think that is what is used inside a bean bag chair. It just looks like them. Anyway... you can get it at any home improvement store or garden center.

Fill the area somewhat slowly, taking time to tap and rattle the can so the insulation settles into the crevices around the soup cans. Not too much though as you don't want to jar the assembly apart. Just a gentle rapping on the outside of the No.10 can should do the trick.

Fill the No.10 can to about one half inch below the rim.

You will want to use your tin snips to cut vertical slits in the No. 10 can from the top rim down about one half inch. This will create tabs that you can then fold down to hold the lid in place. I cut 8 slits so that I had four tabs that folded down and four that stayed upright. The four that fold down hold the lid down and the four that are upright will hold the cooking vessel above the flame.

Once the can is filled with insulation, place the lid on top and fold down the tabs.

You can see from my picture where this first time, my chimney is too tall and sticks up above the height of the vertical tabs. I took it apart and cut down the chimney so that it stuck up above the lid about a quarter of an inch. That leaves a gap between the opening of the chimney and the top of the No.10 can tabs.

Your stove is assembled.

We just need to cut out a small fuel shelf and you'll be ready to fire it up.

Step 7: Make a fuel shelf from Soup Can #4

With the final soup can (soup can #4) you will want to make a small shelf that will fit into the mouth of your stove. This is what the wood will rest on and at the same time allow air to travel into the stove from the bottom.

You will want to cut a "T" shape that is roughly the same width as soup can # 1 with a little wider portion at the top to keep it from sliding all the way inside the stove.

It is easier to see in the photos than to describe it in words.

I will admit that while I originally used a fourth standard soup can, I found it to be inadequate for holding the fuel. I resorted to cutting up a larger can (Chunky sized) so that my fuel shelf was longer and protruded out of the can further. This allowed the weight of the wood that was sticking out of the can to rest comfortably on the shelf without tipping it up and dumping the fuel onto the ground. You will see in the finished version what I mean.

Cut the can to size and slip it into the mouth of the stove. You should have a gap at the top and at the bottom. Without the gap at the bottom the rocket stove will not work.

Step 8: Light that bad-boy up!

Caution: While at first the stove is cool enough to hold in your hand, the outside does heat up and should not be touched with your bare hands. You will be severely burned.

To get the stove going I used some wadded up pieces of regular printer paper shoved into the chimney and lit on fire. This worked fine but I found that the stove really performed well when I used a little bit of paper and also placed a piece of wood down the chimney at the beginning.

The whole reason this system works is due to the thermal differences between the chimney (HOT) and the fuel shelf (COOL).

Getting the whole chimney nice and hot made it work right off the bat. On a second burn I had forgotten this step and it would not hold a flame. Once I put a little fuel down the chimney it worked VERY well. Once the fuel in the chimney burned down low enough then the fuel from the side was all that was needed to maintain a very hot flame.

It burns with little smoke (once lit and burning) and uses very little fuel. I used standard wood shims from a home improvement store that I got for under $2 for about 25 of them. They burn really easily. I broke them in half and they fit well on the fuel shelf.

I cooked some canned chili on the stove (see pictures) with only two of the shims for fuel and probably could have done it with just one.

You will see in the photos that I had a first burn with the tall chimney and small fuel shelf. The photos at the end where I am cooking the chili have the lowered chimney and the larger fuel shelf. I hope those details are not lost in the pictures as they really did make a difference in how well it worked overall.

From start to finish once I had all the cans and tools, it took me roughly an hour to cut, assemble and have my first fire. The whole thing only weighs about a pound or so. It's small and compact. It gives off a lot of heat with very little smoke. Uses little fuel, easy to get lit and easy to put out. My only caution would be that the outside does get hot so you would want to be careful what you put it on and not to touch it once it is burning.

Also, though I did not wear any gloves, nor did I get a single nick or cut, I could see how that could happen easily if you are not careful. A small file to smooth the edges of the cut tin as well as some gloves would not be bad idea. I just didn't really need them myself.

I think this would make an excellent Boy Scouts project or, if you are like me, just a fun little weekend activity with a nice little functional result.

I think a future modification will be to punch a couple of holes in two of the upright tabs and use a wire handle from an old paint can to carry it around with.

I hope you enjoyed this project.

I am from africa and we really need these rocket stoves here especially women. I have taken it upon myself to build these stoves in my country, however I think having an experienced mentor will be grate for me cause rocket stoves have a huge potential here and people are ready to pay a reasonable price for them. I will be glad if anyone is willing to mentor me on how to build a business with these stoves keeping in mind we have extreme limited resource at our disposal here. My mail is &quot;toyomars@gmail.com&quot; thank you.

<p>Nice</p>

<p>I've made lots of rockets, both the simple Winiarski L-rocket and the Ianto Evans J-rocket. I cook and heat with my latest model, right now. This one of yours is really nice; not least because - clearly - you understand the principles which make rockets work so well, and they're faithfully reproduced in this handsome quickie knock-up. I would question, though, sand or clay as insulators; heat sinks, more like. And as you point out, good insulation of the riser tube is critical to make the stove work effectively. Very high combustion temperatures - near 1000 degrees Centigrade for larger-diameter rockets - are an essential design principle; only achievable with a thick layer of good insulation. The proportions which you built in, and the absolutely-vital insulation, are the outcome of long, careful, very much field-tested development periods, by Larry W., and by Ianto independently, and with help from many colleagues. </p><p>Beware the YouTube vids about 'rocket' making! Far too many of the posters clearly don't understand the basic principles of rockets, and make very bad, cargo-cult-style sort-of-rocket-like stoves that don't work right, because they're not built right. Lots of cases, for example, where sand or soil are recommended as high-grade insulators, when they're nothing of the sort. Quite a few cases where the insulation is deliberately left out altogether (kiss of death!). Lots of other examples where the proportions are quite wrong, producing vastly inferior results. Sure, they still cook stuff, after a fashion; but with low temperature flames licking out of the top of the riser, and sooting up your pans. Proper rockets produce super hot carbon-dioxide and water vapour at the top of the riser tube, just as they hit the pan, and virtually nothing else except a very small amount of fly-ash.</p><p>To achieve this final, very hot completion of the fuel burn just at the top of the riser, chimney height needs to be two-and-a-half to three times the diameter; and the more high-grade insulation round the chimney and the inner end of the feed tube the better. Make it three inches thick, at least. Play around with quick, dirt-cheap knock-up rockets like this one, whilst you get the hang of it all. That's what I did. Proper rockets are in a class of their own, better than any standard wood-stove. PROPER rockets, that is! DRY fuel is a great help too.</p><p>BTW, don't try glass-fibre for insulation. A properly built rocket gets so hot, it melts the fibre back from the riser-tube's outer surface. Tried it. Doesn't work! Good insulators are: DRY wood ash, perlite, or vermiculite. They can take the bright-red-to-white-heat.</p><p>Once you're confident that you're up to speed with all this, try making a rocket in stainless steel tube, with 3mm wall thickness. Stainless appears to resist burn-through indefinitely; well, for at least fifteen years in my experience. Four inch diameter is a good starting size. Bigger diameter tube gives a very hot, strong fire, which will need a little more fuel. Still amazingly fuel-economical, though. That's part of the original design-spec. for rockets, for Third World and refugee-camp cooking, where fuel is very scarce, and is often nothing more than dried plant stalks. Tried that with nettle stalks; works amazingly well! The other main design spec. was a very clean burn, to reduce serious lung illnesses to people using firewood long-term for cooking. Only possible at very high temperatures.</p><p>Weld up the parts of the stainless fire tube, rather than just pushing them together. You will need an angle-grinder to cut them to shape. Outer can, to contain the fire-tube and the insulation, can be any suitable mild-steel available. Doesn't have to stand up to the high temperatures and the super-heated oxygen, the way the fire-tube must. </p>

<p>Good Info. Do you have any instructables, videos, or other instruction available?</p>

<p>This presentation is very good and much more clear and detailed than others I looked at. Thanks!!</p>

<p>Okay, I've been having a thought, and I figured I would defer to some experts as I have no experience building rocket stoves. Would it be possible to make a collapsable, portable version of this? To illustrate my idea, I'm envisioning all of the cans, including the no. 10 can, being replaced with some sort of flame retardent, heat resistent flexible tubing like what you would use for dryer ventilation (the kind that can be almost fully compressed) or heat ducts. That, or a design that can fold like a collapsable travel cup. Suggestions are most appreciated :)</p>

<p>Wouldn't it be useful to cut small tabs into soup can #1, so that it will hold on to soup can #2?</p>

<p>Enjoyed this tutorial very much. Well done. Still working on tin can Rocket Stove. If you want to see the grand daddy of Rocket Stoves, check out BCTruck on YouTube! That is where I saw my first Rocket Stove and have been a fan ever since. </p>

Thanks for posting. This was my first instructable and rocket stove. Easy build and well described.

<p>Ok, i took a shot at this oven and i found it a great little work. I did it with a some personal twists partly because of what i had available to work with. First as you might check it's not &quot;closed&quot; of the top, that way you can see i have used ash as insulation, since i had it right on hand (though i originally thought of using sand). Upon its first firing the ash closest to the burner nearly turned to a sort of spongy &quot;stone&quot;.</p><p>I had a problem with fixing the top can of my chimney to the lower &quot;L&quot; part, i used aluminium tape for it but it burned so hot it melted and inflamed the tape so the can got loose. I know it wasn't meant to be done that way but at the moment i didn't remember how to do it according to here but if i redo or do a new oven i already have a few ideas to solve this problem besides the one proposed in this instructable (live and learn).</p><p>No trouble in igniting the first time i used a piece of newspaper imbibed with some alcohol and a couple of sticks of well dried wood trough the shelf, lighted it with a wooded match. It burn really well so well in fact that i was frightening, in the 20 min i was feeding it, it burned loads of twigs which surprised me a bit, since i thought it wouldn't burn so fast and i had the idea it was efficient as in &quot;low fuel consumption&quot;. The outside wall grew really hot and even after the fire inside was dead the outside kept on being very hot for quite a while.</p><p>Another problem i didn't expect was the amount of ash it produced, so much in fact that after a while i stopped feeding the fire because it was having a hard time to let air through. From what I've read about this type of oven i had the idea that it didn't produce much ash. Anyways i'm planing to place a second shelf like part to the bottom of the feed can so i can, on occasion, remove the acumulated ash before it strangles the fire an burns it out.</p><p>Other than that it worked out great and it shows great promess to be a little portable stove (it weights less than 4 pounds) to take on my beach/camping days, for cooking/grilling/heat a bit of food on the spot as well as providing a little heat if the party drags on throughout the night.</p>

<p>A good way to make this a heavy duty stove would be to use concrete and perlite mixed.I think that's my next project.Thank you!</p>

<p>Made it with bigger cans for prototype. (what I had) Will make the next like yours.</p><p>Thank you for posting this.</p>

This is going to be my next rocket stove. I recently built one out of 4 cinder blocks but it is not as effective because it lacks insulation. I have not tinkered enough with it but have at least succesfully made tea. Thank you for the new project, looks like a lot of fun!

awesome.does it take long to cool down after its been burned out? just curious for snowboarding/camping out as to how long before i can pop it back in my backpack and ride out.

I would think that if you shoved it in the snow, not more than a few minutes. Because it is so well insulated it never gets too hot.

I am going to build this. I am a boyscout so this will come in handy

What temperatures does this little stove generate on average?

I have not put a gauge on it. I have no idea.

how has the ash build up been?

Since it burns so hot and completely, there is not really any ash buildup. It burns the fuel completely.

I am not getting good flames. I think can #1 may be too far into #2 in mine. Do you think trimming the portion of #1 that is blocking the chimney would help? Seemed like it was just a bit choked. Didn't want to adjust something that would mess it up. Great build, like you said, very little ash left.

Yes. Definitely cut it down. Also, be sure to pre-load the chimney with paper when getting it lit. You want to pre-heat the chimney so it is nice and hot before it will really hold a flame.

Built this handy little stove the other day. We didn't have any perlite, and the kids' sandbox was wet, so I used some &quot;Roxul&quot; insulation. I traced the bottom of the can on to the insulation, then cut them out using an old bread knife. I then traced the bottom of a soup can into the middle of my insulation circles, then removed sections so that they fit snugly around the chimney/feeder tube parts. I used high temp silicone to seal any gaps in the chimney. <br>The stove works very well. <br>Thanks for the instructable!

thanks for that. Gonna try it this weekend. out on the cycle today to scrounge up a big can

Hi Darrin, <br>This instructable is a little old now so I don't know if you're still watching the comments. The problem I have is that the Perlite I am using is a range of different sizes and some of it is very small and nearly a powder. How do you stop this stuff pouring out the cracks. I made one stove like this and when I encountered this problem I used a steel putty. That was pratley's putty that dries out to be of near steel strength. The problem is that it gave of black smoke from the chimney seal that I was not comfortable cooking food with. So I am now set up to try this again and any suggestions would be welcome. <br> <br>Currently I am thinking of using aluminium foil with some wire to hold it in place. Any thoughts? <br> <br>Any suggestions would be most welcome. <br> <br>Regards, Martin.

Sorry I hadn't seen this earlier. <br>I used brand new Perlite and it was still quite fluffy and round so I didn't have the problem of it creeping out of the seems. I would think you could pretty much wrap the whole thing in aluminum foil and be good to go. <br>The way that I cut the openings and crimped down the sides for the top make mine quite a tight seal all around.

great 'ible. 1 question. Do you need to insulate under the inner can? Maybe I was not reading carefully, but I didn't see. Thanks

No. Just around the inner can.

great 'ible. 1 question. Do you need to insulate under the inner can? Maybe I was not reading carefully, but I didn't see. Thanks

How easy is it to clean out the ash after a burn?

There is really very little ash left. The rocket stove burns the fuel almost completely. There is no reason to tip it over to empty the ash.

I started investigating pottery clay for this but was told it would just become brittle and break if it was not glazed especially if it was heating and cooling all the time. <br> <br>I was told kiln cement is the way to go. Comes in putty form and dries out and can handle up to 1300 degrees Celsius. Will check it out and report if it is a success. <br> <br>Regards, Martin.

Hi FireCGun, <br>I haven't measured the temperature but mine cooked two rashers of bacon in the same time it took to cook on the gas stove in the kitchen. <br>You could easily cook a bacon and egg breakfast on this stove. I think bigger meals in a dutch oven would be a problem especially due to the requirement of watching the fuel supply into the stove for a long period of time. <br> <br>Regards, Martin.

to what temperature does the stove get up to?

This is great. I will see about doing this with our Boy Scout Troop. And this prevents me from needing to travel with a little coleman stove on some occasions! ;) Thanks.

I'm really impressed with this instructable. I read many and often there are steps which are simply skipped by the author, thinking they're simple, but that leave me stranded. This instructable left me knowing that if I have it by my side I can build this stove. Thanks for the effort you put into making it so clear and detailed it is very much appreciated. <br> <br>Regards, Martin.

Thanks. I appreciate your comments. It was fun to make and to document. I hope you're able to make one yourself. I have had tons of fun with mine.

Thanks Darrin. My son is just turning 8 and I am planning our first camping trip. I think I will get us to make this together as a project to take with us as our camping stove. (I will make sure we have a backup as my construction skills may not be as strong as yours). If I manage to build it I will try and remember to send a photo or two. <br> <br>Regards, Martin.

Foams shouldn't be used for insulating a rocket stove. They will burn/melt/smolder from the intense heat and release toxic smoke. Stick with noncombustables. <br>

Built it. Lit it. Couldn't get it to boil water. Best I got was pin bubbles in the pan and steam. I thought these things were s'posed to boil water at a rolling boil. Did I do something incorrect or this the best I can hope for? Also, standard soup cans are 10 oz. not 8. To get an 8oz. can I had to use 'single-serve' fruit/vegetable, and 'beenie-weenie' cans. The insulator I used was 'just plain ol' dirt/sand off the ground from my camp. Yes, I live in a camp! Propane, sterno, and kerosene are sometimes difficult to aquire but there's plenty of wood' however; open burning, i.e. campfires, are prohibited. (something to do with idiots not knowin' or carin' how to properly build a campfire)

Start next week to make one. I go use salt as isolator. Here in the Philippines is it very cheap.But a little heavy. <br>Thanks for posting this. <br>

Great design,I'm just having a problem with the second can in the chimney. When i try to fit it, the gap/slit i created never closes ive tried a few different ways but i cant seem to figure it out. any ideas?

Hmmm... not sure exactly what the problem is. I did use my hands to shape it quite a bit though. Try that.

Great Instructable!! The next time my friend and I go trekking or camping,we'll make sure that we have that stove with us. Thanks.

thanks this project me and my friend used when we went camping in my backyard <br>(works well cooking hot dogs)